And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. God's almighty word continued to create on the second day. He caused a firm extension, or expansion, to be fixed in the midst of the waters, in the chaos where liquid and vapor were intermingled with the more solid substances. The purpose of this firmament was to keep separate the waters from the waters, as the text next explains.
Related Commentaries of Genesis 1:6
Genesis 1:6
6 And God said, Let there be a firmamentb in the midst of the waters, and let it divide the waters from the waters.